Histamine stimulates secretion of extracellular vesicles with nucleotidase activity in rat submandibular gland.

Background: Extracellular vesicles released by different cells have been isolated from diverse fluids including saliva. We previously reported that rat submandibular glands secrete nanovesicles that catalyze hydrolysis of ATP, ADP and AMP, which are actors of the purinergic signaling system along with adenosine. Extracellular nucleotides like ATP and adenosine are involved in the regulation of inflammatory processes and apoptosis.

Action of anti-M₃muscarinic acetylcholine receptor IgG of primary Sjögren's syndrome on the enzymatic antioxidant system in rat submandibular gland.

Background: We demonstrate that serum immunoglobulin G (IgG) directed against glandular M3 muscarinic acetylcholine receptors (M₃mAChR) and pilocarpine triggers the increment of superoxide dismutase (SOD) and catalase (CAT) and the production of nitric oxide (NO) and prostaglandin E₂(PGE₂).

Methods: Enzyme-linked immunosorbent assay (ELISA) was performed in the presence of the human M₂mAChR synthetic peptide as antigen to detect in serum of pSS patients the autoantibodies. Further, SOD and CAT specific activity and NO were determined chemically in the presence of anti-M₃mAChR IgG and pilocarpine.

H(1)-Receptor activation triggers the endogenous nitric oxide signalling system in the rat submandibular gland.

Background: Histamine is released from mast cells by immunologic and non-immunologic stimuli during salivary gland inflammation, regulating salivary secretion. The receptor-secretory mechanism has not been studied in detail.

Aims: The studies reported were directed toward elucidating signal transduction/second messenger pathways within the rat submandibular gland associated with 2-thiazolylethylamine (ThEA)-induced H(1)-receptor responses.